A versatile technique for radiochemical separation of medically useful no-carrier-added (nca) radioarsenic from irradiated germanium oxide targets

A method for the separation of no-carrier-added (nca) arsenic radionuclides from bulk amounts of irradiated germanium oxide (GeO2) target was developed in view of their potentialities in different biological and nuclear medicine applications. The β− emitting 77As radionuclide, produced by the decay of 77Ge through the natGe(n,γ)77Ge nuclear reaction, was used for standardization of the radiochemical separation procedure. The radiochemical separation was performed by precipitation followed by solvent extraction. About 99% post-irradiation recovery of the GeO2 target material, in a form suitable for reuse in future irradiation, was achieved. The developed method was suitable for the production of nca arsenic radionuclides either as trivalent or pentavalent arsenic in various vehicles which provided flexibility of formulations of different kinds of compound. The overall radiochemical yield for the complete separation of 77As was 90%. The separated nca 77As was of high radionuclidic purity and did not contain detectable amounts of the target material. This method can be adopted for the radiochemical separation of other different arsenic radionuclides produced from GeO2 through cyclotron as well as reactor irradiation.